Plasminogen (PLG)

The protein contains 810 amino acids for an estimated molecular weight of 90569 Da.

 

Plasmin dissolves the fibrin of blood clots and acts as a proteolytic factor in a variety of other processes including embryonic development, tissue remodeling, tumor invasion, and inflammation. In ovulation, weakens the walls of the Graafian follicle. It activates the urokinase-type plasminogen activator, collagenases and several complement zymogens, such as C1 and C5. Cleavage of fibronectin and laminin leads to cell detachment and apoptosis. Also cleaves fibrin, thrombospondin and von Willebrand factor. Its role in tissue remodeling and tumor invasion may be modulated by CSPG4. Binds to cells.', 'Angiostatin is an angiogenesis inhibitor that blocks neovascularization and growth of experimental primary and metastatic tumors in vivo. (updated: April 1, 2015)

Protein identification was indicated in the following studies:

  1. Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
  2. Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
  3. D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.

Methods

The following articles were analysed to gather the proteome content of erythrocytes.

The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.

PublicationIdentification 1Uniprot mapping 2Not mapped /
Obsolete
TrEMBLSwiss-Prot
Goodman (2013)2289 (gene list)227853205992269
Lange (2014)123412347281224
Hegedus (2015)2638262202352387
Wilson (2016)165815281702911068
d'Alessandro (2017)18261817201815
Bryk (2017)20902060101081942
Chu (2018)18531804553621387

1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry

The compilation of older studies can be retrieved from the Red Blood Cell Collection database.

The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.

No sequence conservation computed yet.

This protein is annotated as membranous in Gene Ontology.


Interpro domains
Total structural coverage: 98%
Model score: 100

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VariantDescription
PLGD
dbSNP:rs1049573
dbSNP:rs4252070
dbSNP:rs4252186
dbSNP:rs2817
PLGD
PLGD
dbSNP:rs4252187
PLGD
dbSNP:rs4252119
dbSNP:rs1804181
dbSNP:rs4252125
dbSNP:rs4252128
dbSNP:rs4252129
PLGD
PLGD
PLGD
dbSNP:rs17857492
PLGD

The reference OMIM entry for this protein is 173350

Plasminogen; plg angiostatin, included
Microplasmin, included

DESCRIPTION

Plasminogen (PLG) is a circulating zymogen that is converted to the active enzyme plasmin by cleavage of the peptide bond between arg560 and val561, which is mediated by urokinase (PLAU; 191840) and tissue plasminogen activator (PLAT; 173370). The main function of plasmin is to dissolve fibrin (see, e.g., FGA, 134820) clots. Plasmin, like trypsin, belongs to the family of serine proteinases (Miyata et al., 1982; Forsgren et al., 1987).

CLONING

Forsgren et al. (1987) isolated a full-length cDNA corresponding to the PLG gene from a human liver cDNA library. The deduced 791-residue nonglycosylated protein has a calculated molecular mass of 88.4 kD. After conversion, active plasmin consists of a heavy (A) and light (B) chain that have molecular masses of 63.2 and 25.2 kD, respectively. The N terminus of plasminogen corresponds to the heavy chain and contains 5 tandem repeats called kringles, which may mediate fibrin binding. The proteolytic active center of plasmin is located within the C-terminal light chain. McLean et al. (1987) found that the human apolipoprotein(a) gene (LPA; 152200) shows striking similarities to the human PLG gene. In addition, both genes are located on chromosome 6q27. Degen et al. (1990) isolated cDNA for the mouse Plg gene. - Angiostatin O'Reilly et al. (1994) isolated a novel angiogenesis inhibitor, termed 'angiostatin,' from the urine and plasma of mice with lung carcinoma. It was found to be a 38-kD internal fragment of mouse plasminogen that contains the first 4 kringle structures. The circulating protein mediated the suppression of remote tumor metastases in mice by inhibiting the growth of capillary endothelial cells. Human angiostatin had the same effect on mouse tumors. Cao et al. (1996) demonstrated that recombinant fragments of angiostatin had inhibitory activity on capillary endothelial cell proliferation in vitro. Gately et al. (1996) showed that angiostatin is produced by the proteolytic cleavage of plasminogen by a serine protease produced by several human prostate carcinoma cell lines. - Microplasmin Wu et al. (1987) described the preparation and purification of a fully functional human microplasmin derived from native plasmin. Microplasmin is formed from the autolytic cleavage of plasmin in an alkaline solution. Microplasmin consists mainly of the light chain of native human plasmin and has a molecular mass of approximately 29 kD. Wu et al. (1987) determined that microplasmin consists of 2 polypeptides connected by disulfide bonds. One polypeptide is the 230-residue light chain of plasmin and the other is a 31-residue fragment from the C terminal portion of the heavy chain. The calculated molecular mass is 28.6 kD.

GENE STRUCTURE

Petersen et al. (1990) reported that the human plasminogen gene spans about 52.5 kb of DNA and contains 19 exons. They concluded that there is at least one other plasminogen-related gene in the human genome in addition to LPA. Kida et al. (1997) characterized the 5-prime flanking region of the human plasminogen gene and found 3 TATA boxes 550 to 600 bp upstream of the transcription initiation site, a TATA-like sequence (TGTAA) at position -16, and putative binding sites for several transcription factors. The 1.1-kb 5-prime flanking sequence directed basal liver-specific expression in HepG2 cells, and deletion analysis identified 2 negative elements in the PLG promoter.

MAPPING

Eiberg et al. (1984) found a lod score of ... More on the omim web site

Subscribe to this protein entry history

May 12, 2019: Protein entry updated
Automatic update: model status changed

Nov. 17, 2018: Protein entry updated
Automatic update: model status changed

Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated

Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated

Nov. 23, 2017: Protein entry updated
Automatic update: Uniprot description updated

Oct. 27, 2017: Protein entry updated
Automatic update: model status changed

March 16, 2016: Protein entry updated
Automatic update: OMIM entry 173350 was added.

Feb. 24, 2016: Protein entry updated
Automatic update: model status changed

Jan. 28, 2016: Protein entry updated
Automatic update: model status changed

Jan. 25, 2016: Protein entry updated
Automatic update: model status changed